MANUFACTURING

2 Introduction  Consumers are people who buy and use the items made in factories – soap, food, shoes, cars, and books  Industrial revolution in late 1700s – new methods of manufacturing  The first factories in the world made textiles in England and Scotland between 1750 and 1800  Factory’s power usually came from rivers that turned water wheels  James Watt later designed a steam engine that could operate machines in factories  Manufacturing is the application of physical and chemical processes to alter the geometry, properties, and/or appearance of a starting material (raw or semi finished) to make parts or products  Manufacturing also includes assembly of multiple parts to make products  A sequence of operations adds value to the material by changing its shape or properties

3 Introduction Manufacturing Process Starting Material Processed Part People Information Materials Tools & Machines Capital Energy Time

4 Manufacturing Industries  An industry/company may not span the whole cycle of manufacturing – crude raw material to the finished product  Industry consists of enterprises and organizations that produce or supply goods and services  Industries can be categorized as basic producers, converter or fabricator and service industries  The first three categories form a connecting chain  Basic producers cultivate and exploit natural resources and transform these into raw materials – e.g. steel producers  Converters take the output of the basic producer and transform these raw materials into various industrial products and some consumer items – e.g. producers of sheet-metals and plastics  Fabricators fabricate and assemble final products – e.g. manufacturers of automobiles, appliances and garments

5 Manufacturing Industries  Service industry works in parallel with the other three and constitutes the service sector of the economy Basic ProducersConverters and FabricatorsService AgricultureAerospaceAppliancesRepair/Maintenance PetroleumAutomotivePharmaceuticalsEducation FishingBeveragesPublishingHotel MiningChemicalsTextilesTourism ForestryElectronicsTire and RubberTransportation

6 Manufacturing Industries  Another classification of manufacturing firms may be by the quantity of the products they make  Job shop production, batch production and mass production

7 Resources for Manufacturing  Companies use a complex but coordinated setup of all the basic resources  People –Large companies employ a huge workforce because they manufacture several products at the same time –People to put forward the requirement of a new product –Research engineers and design engineers/drafters –Development engineers decide the steps of manufacturing the product –They make a prototype (a test version of the product ) of the new product before going onto the full scale or mass production –Production engineers implement the plan given by development department –Hundreds of laymen workers work in the production department –These workers may be working on or repairing and maintaining the machines –Skilled and qualified people are required for quality control –Planning, managing warehouses, dispatching etc –Marketing and distribution of the product in the local and international markets

8 Resources for Manufacturing  Information –Trends in the market –Different type of materials, their costs and quality standards –Mechanical drawings of different parts –Knowledge of manufacturing processes –Companies may launch new research projects in collaboration with universities  Materials –It is not always a raw material – materials in the natural state, e.g. iron ore, trees, and cotton –Steel sheets come from iron ingots made from coal, limestone and iron ore –Companies often make a trade-off between the cost and the quality of a material

9 Resources for Manufacturing  Tools and Machines –A tool changes the shape of material or fastens it together –Hand tools are those that use the power of our hand or arm – hammer and pliers –A power tool uses a small motor and is usually held in our hands – Electric drills –Jigs and fixtures facilitate the process of manufacturing – devices used to locate and hold work pieces. –Machines are usually operated by electric motors – bending, cutting, drilling, grinding, and hammering –Modern manufacturing processes run under program and feedback control A jig used in carpentry shop

10 Resources for Manufacturing  Energy –Mostly in the form of electricity –Thermal power – electricity from fossil fuels, i.e. coal, oil and natural gas –Own power source or near the government power supply – low transmission costs –A chemical plant can use its waste heat energy to generate steam – co-generation  Capital –Buy land, build factories, purchase equipment, pay workers, maintain machines, and advertise their products –A company may sell shares of stock –Capital may also come from a venture capitalist –Venture capital is money used to finance the costs of starting a new company  Time –Productivity is how quickly and cheaply a product is made –F. W. Taylor suggested the idea of scientific management – study every movement that a worker made

11 Industrial Materials  Four basic categories – metals, ceramics wood and polymers  Other useful materials are natural rubber/leather, glass, cotton, silk and wool  Criteria for selecting the right material – properties of the material, its deterioration-rate and its cost  Manufacturing process that can be used to make products depend on the mechanical and physical properties of the materials  Metals –Alloys are composed of two or more elements –Metals can be divided into two basic groups: (1) ferrous, and (2) nonferrous –Steel contains 0.02 to 2.11 % carbon. It may also have manganese, chromium and nickel to enhance the properties of the metal –Cast iron is an alloy of iron, carbon (2 to 4 %) and silicon (0.5 to 3 %) –Gray cast iron is used in blocks and heads of internal combustion engines

12 Industrial Materials  Ceramics –Compounds of metallic (or semi metallic) and nonmetallic elements – oxygen, nitrogen, ad carbon –Traditional ceramics – clay for brick, tile and pottery, silica for glass products and alumina and silicon carbide for abrasives used for grinding –Newer ceramics – tungsten carbide and titanium carbide for cutting tools and grinding abrasives –Crystalline ceramics are formed from powders and then sintered –Sintering – heating to a temperature below the melting point to achieve bonding between the powders

13 Industrial Materials  Wood –Natural wood can be classified into two forms – hardwood and softwood –Hardwood – trees that lose their leaves in winter, such as maple, oak and walnut –Softwood – evergreen trees such as fir, pine and redwood –Plywood is made by gluing together a number of thin veneers or plies of softwood or hardwood. There is always an odd number of veneers –Hardboard is made from wood fiber extracted from chips and pulped wood waste – a cheaper option than plywood Plywood Hardboard

14 Industrial Materials  Polymers –A compound formed of repeating structural units –They consist of carbon plus one or more other elements such as hydrogen, nitrogen, oxygen, and chlorine –Thermoplastic polymers soften when heated and when cooled, they are hard again – polyethylene bags, PVC pipes and nylon –Thermoset polymers char and burn when heated – plastic cups and dishes made of melamine.